Room type air conditioners typically have an indoor section and an outdoor section. The indoor section is responsible for cooling and dehumidifying the indoor room air while the outdoor section is responsible for exhausting heat into the outdoor environment. The indoor and outdoor sections each have a heat exchanger coil and a fan, and each has a return air opening and a discharge opening. A grille structure is normally installed over each section to prevent the entry of foreign objects, while allowing the free flow of air to and from the sections as well as for aesthetic considerations. It is common practice to have associated with the indoor grille structure a filter element, through which the indoor air passing to the indoor coil must pass. Such a filter is designed to remove substantially smaller contaminants from the air than the indoor grille. Quite often, the indoor grille must be removed from the air conditioner in order to gain access to the filter. Other air conditioners are know which have a rectangular substantially reusable filter which slides into a slot vertically oriented above the inlet grille and the evaporator coil such that the filter is installed or withdrawn by vertically displacing the filter within the slot.
It is deemed desirable to have a filter assembly which easily slides into a slot provided in the indoor grille and which engages retaining structure in the grille. Such is particularly desirable if the indoor discharge assembly is adapted to be oriented in a reversed top to bottom condition wherein the filter slot would be in the lower end of the unit and the filter withdrawn vertically downwardly therefrom.